A wireless communication standard (e.g. the Third Generation Partnership Project—3GPP) may typically specify a set of supplementary services used to enhance the basic services offered to wireless communication devices (also denoted herein as devices or terminals) operating in networks applying the standard. The supplementary services may typically be configured in different ways by a user of the device. As an example, the supplementary service “call forwarding” enhances the basic voice call service of a device, and the user may configure under what conditions, and to which number, incoming calls should be forwarded.
In the example of 3GPP, there was initially only one option for configuration of supplementary services. This first option is defined as a layer three (L3) radio protocol in 3GPP Technical Specification (TS) 24.010 (see e.g. version 11.0.0).
With the introduction of IMS (Internet protocol (IP) Multimedia Subsystem) and subsequently of VoLTE (Voice over LTE (Long Term Evolution)), 3GPP added a packet-switched option for configuration of supplementary services. This second option is based on the XCAP XML-over-HTTP protocol (where XCAP stands for XML (Extensible Markup Language) Configuration Access Protocol and HTTP stands for HyperText Transfer Protocol) and is defined in 3GPP TS 24.623 (see e.g. version 11.1.0). See also GSMA PRD IR.92 (GMS (Global System for Mobile communication) Association Permanent Reference Document IR.92, e.g. version 7.0 of Mar. 3, 2013) for more information regarding IMS and VoLTE.
For simplicity, these two protocols will also be referred to herein as “24.010” and “XCAP”, respectively.
The XCAP-based supplementary services were designed to mirror the functionality already available in 24.010-based supplementary services, but the two protocols were not designed to be used together. In particular, while some wireless communication devices are designed to be able to use any of the two protocols for supplementary services configuration, the network node(s) implementing 24.010-based supplementary services configuration is typically not adapted to also handle XCAP-based supplementary services configuration (and vice versa for the network node(s) implementing XCAP-based supplementary services configuration).
Thus, networks that support both 24.010 and XCAP will store supplementary service settings in two separate network nodes, which may or may not be geographically separated. This scenario illustrated in FIG. 1, where three wireless communication devices 110, 120, 130 are illustrated while operating in connection with a wireless communication network (NW) 100, e.g. an IMS network.
The device 110 is adapted to configure supplementary services using a first protocol (e.g. 24.010-based) as illustrated by 111, and the corresponding supplementary service settings are stored by the network 100 in a first network node 140.
The device 130 is adapted to configure supplementary services using a second protocol (e.g. XCAP-based) as illustrated by 131, and the corresponding supplementary service settings are stored by the network 100 in a second network node 150.
The device 120 is adapted to configure supplementary services using any of the first and second protocols, and the corresponding supplementary service settings are stored by the network 100 in the first or second network node as applicable depending on which protocol was used.
To ensure backwards compatibility for older devices, it is typically expected that wireless communication networks that support XCAP-based configuration of supplementary services also continues to support 24.010-based configuration, at least for the foreseeable future. Similarly, newer devices that are adapted to use XCAP-based configuration of supplementary services will typically also support 24.010-based configuration, at least while there are wireless communication networks where XCAP-based configuration is not supported.
In some deployments of wireless communication networks (where a particular deployment may, for example be by a particular operator), XCAP-based configuration may only be supported in parts of the network and/or 24.010-based configuration may only be supported in parts of the network. Other parts of the network may support both XCAP-based configuration and 24.010-based configuration. The various parts referred to above may, for example, be geographical parts.
For example, it may not be possible to use XCAP-based configuration for a device currently associated with a network cell that does not support data traffic. Another example where it may not be possible to use XCAP-based configuration is when a device is currently associated with a network cell that does not allow a secondary data connection to the operator's internal network.
In such deployments—where the support regarding which protocol (e.g. XCAP and/or 24.101) is possible to use for supplementary services configuration varies throughout the network—a device that supports both protocols will typically have to switch between different protocols when performing cell switches (e.g. re-selection or handover) between cells with different supplementary services configuration support.
This, together with the fact that supplementary service settings related to different protocols are stored in separate network nodes, results in that a device may have different supplementary service settings related to it, each configured using a respective protocol and stored in a respective network node. From the user perspective, this situation will cause unexpected and/or unwanted behavior. For example, the user typically expects operation according to the latest supplementary services configuration, while actual operation may be in accordance with an earlier supplementary services setting due to a switch being made after the latest configuration between cells with different support of configuration protocols.
C1-132970 “Domain for supplementary services configuration”, by Qualcomm Incorporated, 3GPP TSG CT WG1 meeting #84, Vienna, Austria, Aug. 5-9, 2013 recognizes a need to synchronize the supplementary services settings between CS (circuit switched) and PS (packet switched) domain and that such synchronization lead to additional network complexity.
US 2013/0194976 A1 discloses a method of interworking a packet network and a circuit network with regard to supplementary services.
At present, there is no standardized mechanism available to synchronize supplementary services settings stored in the network node associated with XCAP-configuration with those stored the network node associated with 24.010-configuration, or vice versa. Furthermore, any potential such mechanism typically increases the complexity of the network. In addition, network updates will typically be required for the implementation of such mechanisms.
Therefore, there is a need for methods and arrangements for supplementary services configuration with desired performance in network deployments where different cells of the network support different selections of protocols for configuration. An example desired performance comprises that a latest configuration of supplementary services should, preferably, apply.